Infinite Refractive Index Gradient IOL for Multifocal Vision
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current intraocular lenses (IOLs) for aphakic eyes lack multifocal visual imaging capabilities without glasses, suffer from optical distortions, halos, and reduced visual acuity due to limited focal points and fixed focus, failing to replicate the accommodation and depth perception of a natural lens.
Innovation Solution
Development of a multifocal IOL with a true infinite refractive index gradient (IRIG) made from polymeric materials, mimicking the natural lens to provide continuous accommodation for near, intermediate, and far vision, minimizing optical distortions and halos by creating a gradient of refractive indices from the edge to the center.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a single focus optic portion is used in IOL, then the IOL structure is simple and manufacturing is easier, but the visual acuity is limited and glasses are required for distance changes
Solution Approach 1:
The patent applies local quality by creating different refractive index zones within the IOL optic portion. The gradient refractive index profile varies continuously from the center to the edge of the lens, with the center having a higher refractive index and the edge having a lower refractive index. This spatial variation in optical properties enables multifocal functionality without requiring multiple separate optical elements, thus maintaining manufacturing simplicity while achieving superior visual acuity across multiple distances.
2Adaptability or versatility
If bifocal IOL design is used, then multifocal visual imaging is provided, but each focal point represents only about forty percent of available light and twenty percent is lost to scatter
Solution Approach 1:
The patent employs parameter changes by implementing a continuous gradient refractive index profile instead of discrete bifocal zones. The refractive index varies continuously from approximately 1.406 at the edge to 1.610 at the center, creating infinite focal points rather than just two. This continuous parameter variation distributes light more efficiently across multiple focal distances, reducing light scatter and improving overall light utilization while providing adaptability for near, intermediate, and far vision.
3Adaptability or versatility
If discrete RI interfaces or changes between optical zones are used, then multifocal points are created, but distortion, loss of depth of field, and unwanted images such as halos and bright spots are produced
Solution Approach 1:
The patent applies continuity of useful action by establishing a continuous gradient refractive index profile throughout the optic portion without discrete interfaces or abrupt transitions. The refractive index changes smoothly and continuously from the center to the edge, eliminating sharp boundaries that cause light scattering, halos, and optical distortions. This continuous gradient maintains uninterrupted light propagation while still creating the necessary multifocal points for distance accommodation.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The IRIG IOL enhances visual acuity by restoring accommodation and contrast sensitivity, offering improved near, intermediate, and far vision without the need for glasses, reducing optical aberrations and light scattering.
Implementation Method 1
making an IOL with a true infinite refractive index gradient (IRIG) would provide patients with improved near, far and intermediate vision
Implementation Method 2
creating a gradient of refractive indices from the edge to the center
Data Source
AI summary
Infinite gradient refractive index ophthalmic devices and methods of making same. The method involves diffusing a monomer which polymerizes to a lower or higher corresponding opposite refractive index polymer into a lower or higher index polymer structure and polymerizing same to create the gradient structure. The resulting polymeric structure is used to manufacture ophthalmic devices, e.g., intraocular lenses.